In May, Markham typically sees daytime highs of 18.1°C and overnight lows around 6.7°C. Compared to the annual average high of 11.6°C, May runs +6.5°C.
May in Markham averages a daytime high of 18.1°C and an overnight low of 6.7°C.
May runs +6.5°C compared to Markham's annual average high of 11.6°C, ranking #5 of 12 months by warmth.
Plan for daytime highs near 18.1°C and cooler evenings around 6.7°C.